Halogen addition for improved adhesion of CVD copper to barrier

ABSTRACT

A process is described for depositing a copper film on a substrate surface by chemical vapor deposition of a copper precursor. The process includes treating a diffusion barrier layer surface and/or a deposited film with an adhesion-promoting agent and annealing the copper film to the substrate. Suitable adhesion-promoting agents include, e.g., organic halides, such as methylene chloride, diatomic chlorine, diatomic bromine, diatomic iodine, HCl, HBr and HI. Processes of the invention provide copper-based films, wherein a texture of the copper-based films is predominantly (111). Such films provide substrates having enhanced adhesion between the diffusion barrier layer underlying the (111) film and the copper overlying the (111) film.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not applicable.

BACKGROUND OF THE INVENTION

[0003] This invention relates to a chemical vapor deposition process fordepositing copper films on barrier layer materials, and morespecifically, to improving adhesion between copper and barrier layers.

[0004] CVD (Chemical Vapor Deposition) is a superior process forproducing microscopic metal features on substrates. In this technique, avolatile metal-organic compound in the gas phase is contacted with areasof a circuit where growth of a metal film (e.g., an interconnect) isrequired.

[0005] Copper films have previously been prepared via CVD using variouscopper precursors. One of the best known and most frequently used CVDcopper precursors is the solid compound copper⁺²bis(hexafluoroacetylacetonate) (i.e., copper⁺² bis(hfac)). This highlyfluorinated organometallic precursor is significantly more volatile thanits parent unfluorinated complex, copper⁺² bis(acetylacetonate), and itsease of vaporization has made it a popular choice for CVD processes. Theuse of this compound as a general precursor for CVD copper metallizationwas first described by Van Hemert et al. in J. Electrochem. Soc. (112),1123 (1965) and by Moshier et al. in U.S. Pat. No. 3,356,527. Morerecently, Reisman et al. (J. Electrochemical Soc., Vol. 136, No. 11,November 1989) and Kaloyeros et al. (Journal of Electronic Materials,Vol. 19, No. 3, 271, 1990) in two independent studies evaluated the useof this compound as a copper precursor for electronics applications. Inthese studies, copper films were formed by contacting vapors ofcopper⁺²(hfac)₂, mixed with either an inert gas (argon) or hydrogen andcontacting the mixture with a heated substrate surface. In the case ofusing hydrogen, the copper⁺² atom in the precursor complex is formallyreduced to copper metal, while the hfac⁻¹ ligand becomes protonated toyield a neutral volatile compound. In the case of using an inert gas,the copper⁺² (hfac)₂ is simply pyrolyzed to give copper metal andfragments of the hfac ligand.

[0006] Selective deposition of pure copper films by CVD at lowtemperatures onto metallic substrates using Cu⁺¹ (hfac)L complexes(where L is alkene or alkyne) has been described previously by Norman etal. in U.S. Pat. Nos. 5,085,731, 5,094,701 and 5,098,516. Under certainconditions, blanket (non-selective) deposition can also be achievedusing these precursors (Norman et al., E-MRS proc. B17 (1993) 87-92). Aparticularly effective CVD copper precursor is1,1,1,5,5,5-hexafluoro-2,4-pentanedionato-copper (I)trimethylvinylsilane (hereinafter Cu(hfac)(TMVS)), which is sold underthe trademark CupraSelect by the Schumacher unit of Air Products andChemicals, Inc., Carlsbad, Calif.

[0007] As shown by the following equations, precursors such asCu(hfac)(TMVS) function by a surface catalyzed disproportionationreaction to give a volatile Cu⁺² complex, free olefin and copper metal(wherein (s) denotes interaction with a surface and (g) denotes the gasphase):

2 Cu⁺¹hfacTMVS_((g))→2 Cu⁺¹hfacTMVS_((s))  (1)

2 Cu⁺¹hfacTMVS_((S))→2 Cu⁺¹hfac_((s))+2 TMVS_((g))  (2)

2 Cu⁺¹hfac_((s))→CU_((s))+CU⁺²(hfac)_(2(g))  (3)

[0008] In Equation (1), the complex is adsorbed from the gas phase ontoa metallic surface. In Equation (2), the coordinated olefin (TMVS inthis example) dissociates from the complex as a free gas leaving behindCu⁺¹hfac as an unstable compound. In Equation (3), the Cu⁺¹hfacdisproportionates to yield copper metal and volatile Cu⁺²(hfac)₂.

[0009] Despite the foregoing developments, the integrated circuit (IC)industry is presently experiencing difficulty forming adherent copperfilms on barrier layer materials such as Ta, TaN, TiN, etc., viachemical vapor deposition (CVD) with fluorinated precursors, includinghfac-based precursors such as Cu(hfac)(TMVS). A variety of solutions tothis problem have been proposed.

[0010] For example, Gandikota et al., 50 Microelectronic Engineering547-53 (2000), purports to improve adhesion between a CVD copper thinfilm and barrier layers by: (a) depositing a copper flash layer on thebarrier layer by physical vapor deposition (PVD) prior to chemical vapordeposition, or (b) annealing the CVD copper layer after deposition. Seealso Voss et al., 50 Microelectronics Engineering 501-08 (2000).Unfortunately, these methods are not acceptable to the IC industrybecause they add to the equipment requirements for the copper depositionstep. In addition, annealing, particularly at elevated temperatures, canhave deleterious effects on the overall product.

[0011] WO 00/03420 (Paranjpe et al.) discloses improving CVD copperadhesion to a diffusion barrier layer by: (a) annealing the seed layerdeposited on the diffusion barrier layer surface, or (b) providing aninert seed layer (e.g., comprising a noble or passivated metal) on thediffusion barrier layer surface.

[0012] WO 99/63590 (Bhan et al.) discloses improving CVD copper adhesionto a diffusion barrier layer by: (a) providing a copper seed layercontaining water on the diffusion barrier, and (b) annealing the seedlayer with heat or ion bombardment.

[0013] U.S. Pat. No. 5,909,637 to Charneski et al. discloses a copperCVD method comprising exposing a surface of a diffusion barrier layer toa reactive gas species to purportedly replace high-energy molecularbonds on the surface with low-energy bonds between the reactive gasspecies and the surface. This is said to change the surfacecharacteristics of the exposed copper-receiving surface to promote theformation of bonds between the copper-receiving surface and coppersubsequently deposited by CVD, whereby copper adhesion to the diffusionbarrier is improved.The low-energy bonds are said to promote theadhesion of copper to the diffusion barrier layer.

[0014] U.S. Pat. No. 5,913,144 to Nguyen et al. discloses a process forimproving adhesion of CVD copper to barrier layers, comprising the stepsof: exposing the copper-receiving surface to a reactive oxygen species;oxidizing a thin layer of the diffusion barrier material surface inresponse to the oxygen exposure; and stopping the exposure of thediffusion barrier material to the oxygen before the oxide layer exceedsapproximately 30 angstroms, whereby the relatively thin oxide layerprepares the diffusion barrier material receiving surface for adhesionto copper.

[0015] U.S. Pat. No. 5,918,150 to Nguyen et al. discloses the use of aninert gas to remove contaminating byproducts of the disproportionationreaction which deposits copper on the diffusion barrier layer. Lowenergy ions of the inert gas are impinged upon the contaminated copperlayer to physically displace contaminants thereon and provide a cleancopper surface for additional copper CVD.

[0016] U.S. Pat. No. 5,948,467 to Nguyen et al. discloses a two-stepdeposition process, wherein the first step comprises copper CVD at a lowdeposition rate and the second step comprises copper CVD at a highdeposition rate. The initial slow deposition rate is said to alloworganic solvents within the precursor vapor to be carried out of theprocess chamber instead of being captured within the film at theinterface between the diffusion barrier layer and overlying CVD copper.This is said to provide improved adhesion of CVD copper to theunderlying diffusion barrier layer.

[0017] U.S. Pat. No. 5,953,634 to Kajita et al. discloses a two-stepdeposition process, wherein the first step comprises copper CVD in thepresence of an oxidizing gas and the second step comprises copper CVD inthe absence of the oxidizing gas.

[0018] JP-A-10-98043 (Nguyen et al.) discloses a method for oxidizingthe surface of the diffusion barrier layer to improve CVD copperadhesion thereto.

[0019] U.S. Pat. No. 6,015,749 to Liu et al. discloses improving CVDcopper adhesion to diffusion barrier layers by implanting germanium ionsin a copper seed layer deposited on the diffusion barrier layer surface.

[0020] In addition, the inventors filed on Aug. 15, 2000 U.S. patentapplication Ser. No. 09/638,586, which discloses improving CVD copperadhesion to diffusion barrier layers by treating a diffusion barrierlayer surface and/or a deposited film with a donating molecule selectedfrom the group consisting of a proton-donating molecule and ahydrogen-donating molecule (e.g., methylsilane).

[0021] Although the inventors are aware of references teaching the useof certain halogen-containing molecules in microelectronic processing,these references do not disclose the use of halogen-containing moleculesto improve CVD copper adhesion to barrier layers. For example, U.S. Pat.No. 5,599,425 to Langendijk et al. discloses the use of certain organicchlorides in silicon processing, but does not teach that depositingcopper on a barrier layer in the presence of a halogen-containingmolecule can improve adhesion of the copper to the barrier layer.

[0022] Hwang et al., 3(3) Electrochemical and Solid-State Letters 138-40(2000) discloses that certain iodine-containing molecules, includingethyl iodide, methyl iodide, tertiary-butyl iodide and molecular iodine,can minimize the roughness of surfaces deposited by copper MOCVD. Theresulting films are said to be predominantly (111)-oriented, regardlessof the deposition conditions, provided that iodine is adsorbed to thegrowing film surface. Hwang et al. does not disclose thathalogen-containing molecules can improve the adhesion of the copper to abarrier layer.

[0023] Despite the foregoing developments, there remains a need in theart for alternative solutions to the CVD copper adhesion problem.

[0024] All references cited herein are incorporated herein by referencein their entireties.

BRIEF SUMMARY OF THE INVENTION

[0025] Accordingly, the invention provides an improved copper CVDprocess, wherein the improvement comprises treating at least one of thesurface and the copper film with an adhesion-promoting agent comprisinga halogen other than fluorine, and annealing the copper film to thesurface. The inventive process provides copper-based films, wherein atexture of the copper-based films is predominantly (111). Such filmsprovide substrates having enhanced adhesion between the diffusionbarrier layer underlying the (111) film and the copper overlying the(111) film.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

[0026] The invention will be described in conjunction with the followingdrawings in which like reference numerals designate like elements andwherein:

[0027]FIGS. 1A is an X-ray Photoelectron Spectroscopy (XPS) spectrum ofa sample before annealing; and

[0028]FIG. 1B is an XPS spectrum of a sample after annealing.

DETAILED DESCRIPTION OF THE INVENTION

[0029] The invention improves upon conventional processes for depositinga copper film on a substrate surface by chemical vapor deposition of acopper precursor. In preferred embodiments, the copper precursor and anadhesion-promoting agent are provided in the CVD chamber simultaneously,resulting in a combined reaction occurring at the interface, whichpromotes adhesion. Alternatively, addition of the adhesion-promotingagent to the CVD chamber can commence prior to addition of the copperprecursor to the CVD chamber and preferably continue during at least theinitial stages of CVD copper deposition using the precursor. Inembodiments wherein the adhesion-promoting agent and the copperprecursor are co-deposited, the adhesion-promoting agent is preferablyadded for only a short period of time at the start of the CVD copperdeposition, with the remainder of the copper film being grown undernormal deposition conditions. Co-deposition of the adhesion-promotingagent is maintained until a continuous copper film is produced on thesubstrate. After forming a continuous film of copper on the barrierlayer, the flow of the adhesion-promoting agent is stopped and copperdeposition is permitted to continue unaided. When a film of the desiredthickness is achieved the deposition process is terminated. The film andsubstrate are then annealed.

[0030] In embodiments, the copper precursor and the adhesion-promotingagent are provided in a homogeneous mixture, which can containadditional ingredients (e.g., an inert gas medium).

[0031] The adhesion-promoting agent is preferably a molecule thatcontains one or more halogen species. Preferably, the adhesion-promotingagent is free of fluorine. More preferably, the adhesion-promoting agentcomprises a volatile organic halide and is free of fluorine.Particularly preferred examples of adhesion-promoting agents includemethyl chloride, methylene chloride, methyl bromide, bromochloromethane, bromoiodo methane, bromotrichloromethane, and methyliodide. Amore comprehensive (but still not exhaustive) list of suitableadhesion-promoting agents includes: all methyl chlorides, includingCH_(x)Cl_(y,), where x=0,1,2,3 and y=4-x; all methyl bromides, includingCH_(x)Br_(y), where x=0,1,2,3 and y=4-x; all methyl iodides, includingCH_(x)I_(y), where x=0,1,2,3 and y=4-x; simple halide acid gases,including HCl, HBr, and HI; more complex organic halides, including allchloro-, bromo-, and iodo- group substitutions of ethanes, propanes, andhigher number straight-chain hydrocarbons (particularly dichloroethene,e.g., trans-dichloroethene, which is sold under the trademark Trans-LC®by the Schumacher unit of Air Products and Chemicals, Inc., Carlsbad,Calif.; C₂H₅I; C₂H₅Br; and C₂H₅Cl); cyclic halides; and aromatichalides. In certain embodiments, the adhesion-promoting agent is Cl₂,Br₂ and/or I₂. In certain embodiments, the adhesion-promoting agent andthe overall inventive process are free of iodine.

[0032] The copper precursor used in the inventive process is preferablya fluorinated organometallic compound, more preferably a compoundcomprising hexafluoroacetylacetonate, most preferably Cu(hfac)(TMVS). Inembodiments, the copper precursor can be blended with theadhesion-promoting agent and then used to deposit a film.

[0033] After the CVD copper deposition is completed, the film andsubstrate undergo a short high-temperature annealing step to stabilizethe film. The term “annealing” as used herein means a post-depositionheat-treatment process. The temperature of the annealing step ispreferably about 20 to about 400° C., more preferably 150 to 300° C. Theduration of the annealing step is preferably about 0.1 to about 100minutes, more preferably 5 to 30 minutes. The film and substrate arepreferably annealed under vacuum, in the presence of an inert gas, in apure hydrogen atmosphere, or in a hydrogen-containing (i.e., reducing)atmosphere containing a mixture of 1% to 99% hydrogen and 99% to 1% ofat least one inert gas, such as argon, helium, xenon, neon, krypton, ornitrogen.

[0034] The inventive process provides a copper-containing film, which ismore strongly bound to the barrier layer surface, and better matchedtexturally. This matching is reflected in a XRD pattern for the copperfilm that more closely resembles the (111) texture obtained by PVDdeposition on barrier layers and subsequent electroplating processes.

[0035] Thin films may exhibit a range of atomic order from amorphous tohighly crystalline. A crystalline thin film may form as one singlecrystal with a specific crystallographic orientation relative to thesubstrate, or as an aggregate of crystals, with random or non-randomorientations. XRD is capable of distinguishing highly oriented singlecrystals or polycrystalline films from polycrystalline films with randomorientation. It has been shown that a copper film having (111) as thedominant texture or orientation is preferred because of its resistanceto electromigration. Furthermore, it is widely accepted that copperdeposited via a CVD process tends to form with a preference for a (200)texture on most commonly utilized barriers, such as tantalum, whilecopper deposited via a sputtering process on the same barrier filmstends to orient with a preference for a (111) texture. The inventiondescribed herein not only improves the adhesion of copper but promotesthe growth of copper films with a preference for a (111) texture.

[0036] The interfacial film (or primer coat) is a continuous film,preferably having a thickness of at least 5 angstroms, more preferably 5to 600 angstroms. In embodiments, the interfacial film comprises analloy of copper and the metal(s) on which the diffusion barrier layer isbased (e.g., an alloy of copper and tantalum).

[0037] The process of the invention is suitable for coating a variety ofsubstrates. Preferably, the substrate surface to be coated (i.e., thediffusion barrier layer) comprises at least one member selected from thegroup consisting of tantalum, tantalum nitride, titanium, titaniumnitride, tungsten and tungsten nitride. Tantalum and tantalum nitrideare most preferred.

[0038] Processes of the invention are preferably conducted at ambientpressure or less, more preferably at a pressure of about 10 torr to10⁻¹⁰ torr. Processes of the invention can be conducted at temperaturesbelow room temperature and at temperatures typically achieved duringdeposition of barrier layers. Preferably, the processes are conducted attemperatures from 50-400° C., more preferably from 150-250° C. forCu^(I) precursors and from 150-350° C. for Cu^(II) precursors when theseprecursors are used for bulk film deposition after the interfacial layeris formed.

[0039] The invention will be illustrated in more detail with referenceto the following Examples, but it should be understood that the presentinvention is not deemed to be limited thereto.

EXAMPLES

[0040] The following procedure was used throughout the examples.

[0041] Copper was deposited on tantalum-coated wafers via chemical vapordeposition (CVD) in the manner described below. Since the tantalum wasexposed to air, and thus had a native oxide, the oxide and anyadventitious carbon was removed by light ion sputtering with argon ionsbefore the CVD process. This was performed in an ultra-high vacuum (UHV)chamber (base pressure was 10⁻¹⁰ Torr). The samples were analyzed viaXPS in the UHV chamber to determine the extent of cleaning. Cleaning wascomplete when carbon and oxygen were not detected and the Ta(4f) regiononly revealed tantalum metal. In typical integrated cluster tools, thissputter-cleaning step would not be necessary, as the tantalum would notbe exposed to air before the deposition step.

[0042] Incidentally, the inventors have analyzed sputtered samplesbefore and after the sputtering process via atomic force microscopy andhave not found a change in the surface roughness. These sputter-cleanedsamples have surfaces similar to PVD, IMP, or sputter deposited barrierlayer surfaces. Since the surface roughness does not change, thesputtering does not have a direct effect on the adhesion of the CVDcopper.

[0043] After sputtering, the sample was transferred in vacuo to the CVDreactor. The sample was typically heated to the deposition temperaturein an Ar ambient.

[0044] In the CVD reactor, the typical deposition conditions were: 190°C. sample surface temperature, 1.5 Torr (0.03 Torr CVD chamber basepressure), and 40 sccm helium flowing through a bubbler ofCu(hfac)(tmvs) held at 40° C. All delivery lines and the walls of theCVD reactor were maintained at 60° C. Gas and vapor flow were firstinitiated into a bypass to stabilize flow before introducing these intothe CVD reactor.

[0045] A conventional tape pull test (ASTM Standard D3359-95a, “StandardTest Method for Measuring Adhesion by Tape Test”) was used to evaluatethe adhesion of the films grown in the examples. The tape used in theexamples was Permacel #99 tape.

COMPARATIVE EXAMPLE

[0046] CVD copper films were deposited in accordance with the foregoingprocedure. The maximum CVD copper film thickness produced in the abovemanner that adhered to the sputter-cleaned tantalum surface wasapproximately 1800 Å. Films having greater thicknesses delaminated.Films grown in the above manner had a mixed texture of (111) and (200)as determined by X-ray Diffraction (XRD) analysis (see Table 1, below).

Example 1 Sample Deposition with Methylene Chloride

[0047] The tantalum surface was sputter cleaned and the sampletransferred in vacuo to the CVD reactor, as in the previous examples.The sample was heated to 190° C. in an Ar ambient. An initialinterfacial layer was formed during a two-minute deposition in amethylene chloride and Cu(hfac)(tmvs) ambient. After the second minuteof deposition, the methylene chloride flow was terminated and a bulkcopper film was grown to a thickness of ˜7700 Å. At the completion ofthe deposition process, the flow of the copper-containing precursor wasstopped and the film was annealed at 350° C. in an argon atmosphere for50 minutes. This film had 100% adhesion. Films grown in this manner hada predominance of (111) texture, with a small amount of (200) and (220)texture (see Table 1 below). TABLE 1 Relative (111) Relative (200)Relative (220) Example Intensity Intensity Intensity Comparative 10046.8 26.6 Example 1 100 26.7 ± 0.1 11.4 ± 0.5 With MeCl

[0048] Using this procedure, films up to three microns in thickness weregrown and found to possess good adhesion.

Example 2 Interfacial Alterations from Co-Deposition of MethyleneChloride

[0049] To better understand the interfacial chemistry responsible forthe improved adhesion, three samples were prepared and examined byhigh-resolution XPS surface analysis. The conditions employed for SampleA consisted of a two-minute deposition with only Cu(hfac)(TMVS) (underthe deposition conditions utilized, two minutes enabled formation of acontinuous surface film of copper). Sample B was prepared byco-depositing methylene chloride and Cu(hfac)(TMVS) for two minutes,followed by a 42-minute anneal in Ar. Sample C was identical to SampleB, without the annealing step. These samples were generated to examinethe interfacial surface present immediately before bulk copper filmgrowth. All samples were exposed to ambient during transfer to the XPSsystem, so after initial analysis a mild sputter was performed (toremove surface oxide and contaminants) and the analysis was repeated.The results are summarized in Table 2, below. TABLE 2 Relative AtomicPercent Sample I.D. Condition F Cu Cl C O N Si Sample A As Received 13.034.2 0.5 22.1 30.2 ND ND (Comparative Ex.) After Mild Sputter ND 92.8 ND 4.8  2.4 ND ND Sample B As Received ND 38.4 0.9 49.9 10.8 ND ND AfterMild Sputter ND 88.7 ND  8.9  2.4 ND ND Sample C As Received  1.8 40.52.8 22.3 23.8 8.8 ND (Comparative Ex.) After Mild Sputter ND 94.2 ND 5.8 ND ND ND

[0050] This analysis shows that the co-deposition of Cu(hfac)(TMVS) withmethylene chloride virtually eliminates fluorine-containing species,i.e., C_(x)F_(y), present at the interfacial surface. The presence offluorine at the copper-tantalum interface is believed to greatly reducefilm adhesion.

Example 3 Interfacial Alterations from Annealing Step

[0051] A sample was prepared as outlined above with a two-minuteco-deposition of Cu(hfac)(TMVS) and methylene chloride. After thisinterfacial layer was deposited it was transferred in-vacuo to an XPSsystem and analyzed for surface chemical composition. The sample wasthen reintroduced to the CVD chamber and annealed for 30 minutes at350EC. The sample was then again transferred in-vacuo to the XPS systemand re-analyzed for surface chemical composition. The substrate tantalum4 f emission regions for the two analyses are shown in FIGS. 1A and 1B.

[0052] As shown in FIG. 1A, before annealing no tantalum is visible atthe film surface (in fact, only copper appears elsewhere in the emissionspectrum). However, after annealing the sample in argon, some of thesubstrate barrier layer tantalum begins to show through the depositedcopper film, possibly indicating some type of alloying between the twometals at the surface (FIG. 1B). This integration of the copper and thetantalum barrier layer at the interface may result in improved adhesionof the overlying bulk copper film.

[0053] While the invention has been described in detail and withreference to specific examples thereof, it will be apparent to oneskilled in the art that various changes and modifications can be madetherein without departing from the spirit and scope thereof.

1. In a process for depositing a copper film on a surface of a diffusionbarrier layer by chemical vapor deposition of a copper precursor, theimprovement comprising treating at least one of said surface and saidcopper film with an adhesion-promoting agent comprising a halogen otherthan fluorine, and annealing said copper film to said surface.
 2. Theprocess of claim 1, wherein said treating is conducted prior to saidchemical vapor deposition of said copper precursor.
 3. The process ofclaim 2, wherein said treating is further conducted during said chemicalvapor deposition of said copper precursor.
 4. The process of claim 1,wherein said treating is conducted during said chemical vapor depositionof said copper precursor.
 5. The process of claim 4, wherein saidtreating and said chemical vapor deposition of said copper precursorcommence simultaneously.
 6. The process of claim 4, wherein saidtreating is terminated after a continuous film is provided on saidsurface.
 7. The process of claim 6, wherein said continuous film has athickness of 5 angstroms to 600 angstroms.
 8. The process of claim 6,wherein said continuous film comprises copper and is substantially freeof metal fluorides.
 9. The process of claim 6, wherein said diffusionbarrier layer comprises at least one member selected from the groupconsisting of tantalum, tantalum nitride, titanium, titanium nitride,tungsten and tungsten nitride, and wherein said continuous film consistsessentially of copper.
 10. The process of claim 9, wherein saidcontinuous film comprises an alloy of copper and said at least onemember.
 11. The process of claim 6, wherein said chemical vapordeposition of said copper precursor is further conducted afterterminating said treating.
 12. The process of claim 1, wherein saidadhesion-promoting agent comprises at least one member selected from thegroup consisting of an organic halide, HCl, HBr, HI, Cl₂, Br₂ and I₂.13. The process of claim 1, wherein said adhesion-promoting agentcomprises at least one organic halide selected from the group consistingof methyl halides, ethyl halides, propyl halides and dichloroethene. 14.The process of claim 1, wherein said adhesion-promoting agent comprisesat least one methyl halide selected from the group consisting ofCH_(x)Z_(y), where Z is Cl, Br or I, x is 0,1,2 or 3 and y is 4-x. 15.The process of claim 1, wherein said adhesion-promoting agent comprisesan organic halide of a straight-chain hydrocarbon having at least fourcarbons, a cyclic halide or an aromatic halide.
 16. The process of claim1, wherein said adhesion-promoting agent comprises methylene chloride.17. The process of claim 1, wherein said process is free of iodine. 18.The process of claim 1, wherein said copper precursor is a fluorinatedorganometallic compound.
 19. The process of claim 1, wherein said copperprecursor comprises hexafluoroacetylacetonate.
 20. The process of claim1, wherein said copper precursor is1,1,1,5,5,5-hexafluoro-2,4-pentanedionato-copper (I)trimethylvinylsilane.
 21. The process of claim 6, wherein said copperfilm is annealed at a temperature of 20 to 400° C., a pressure of thebase pressure of the system to 10 Torr, an atmosphere comprising 0 to100% hydrogen gas and 100 to 0% of at least one inert gas selected fromthe group consisting of argon, nitrogen, helium, neon, krypton andxenon.
 22. The process of claim 21, wherein said copper film is annealedfor 0.1 to 100 minutes.
 23. The process of claim 1, conducted at atemperature of 50 to 400° C.
 24. The process of claim 1, wherein saidcopper precursor contains Cu^(I) and said copper precursor is depositedat a temperature of 150 to 250° C.
 25. The process of claim 1, whereinsaid copper precursor contains Cu^(II) and said copper precursor isdeposited at a temperature of 150 to 350° C.
 26. The process of claim 1,conducted at a pressure of 10 torr 10⁻¹⁰ torr.
 27. The process of claim6, wherein said diffusion barrier layer comprises at least one memberselected from the group consisting of tantalum, tantalum nitride,titanium, titanium nitride, tungsten and tungsten nitride, and whereinsaid continuous film consists essentially of copper and said at leastone member.
 28. The process of claim 6, wherein a texture of saidcontinuous film is predominantly (111).
 29. A substrate comprising acopper-based film produced by the process of claim
 28. 30. The processof claim 1, wherein said copper precursor and said adhesion-promotingagent are provided by a mixture comprising said copper precursor andsaid adhesion-promoting agent.
 31. A composition comprising a mixture ofa copper precursor comprising hexafluoroacetylacetonate and an adhesionpromoting agent comprising at least one member selected from the groupconsisting of an organic halide, HCl, HBr, HI, Cl₂, Br₂ and I₂.
 32. Thecomposition of claim 31, wherein said adhesion-promoting agent comprisesat least one organic halide selected from the group consisting of methylhalides, ethyl halides, propyl halides and dichloroethene.
 33. Thecomposition of claim 31, wherein said adhesion-promoting agent comprisesat least one methyl halide selected from the group consisting ofCH_(x)Z_(y), where Z is Cl, Br or I, x is 0,1,2 or 3and y is 4-x. 34.The composition of claim 31, wherein said adhesion-promoting agentcomprises an organic halide of a straight-chain hydrocarbon having atleast four carbons, a cyclic halide or an aromatic halide.
 35. Thecomposition of claim 31, wherein said copper precursor is1,1,1,5,5,5-hexafluoro-2,4-pentanedionato-copper (I)trimethylvinylsilane.
 36. The composition of claim 35, wherein saidadhesion-promoting agent comprises methylene chloride.